1. Field of Endeavor
The present invention relates to microfluidics and more particularly to a system, for performing parallel nucleic acid sorting, amplification and characterization.
2. State of Technology
There are an estimated 1031 viruses on Earth, making them by far the most abundant biological entities, Identifying and measuring viruses in clinical or environmental sample is extremely challenging. Many viruses are impossible to culture, making traditional phenotypic characterization infeasible. Viruses, compared to micro-organisms and higher life forms, evolve rapidly (particularly RNA viruses) making large fractions of the genome susceptible to genetic drift and shift. It is not unusual for two descendent viruses that produce similar disease to have multiple mutations across the genomes. With no gene fidelity, profiling (including detection) cannot be accomplished using conserved sequences. Some insight into this problem has been gained through viral metagenomics. Viral metagenomics is a rapidly emerging field that has produced relatively small numbers of publications. There are, to the best of our knowledge, six published viral metagenomic libraries. Only one of these studies included RNA viruses. Samples were collected from human faeces, marine sediment, and seawater. Over 65% of metagenomic sequences had no homologues in the non-redundant databases, a tribute to the paucity of diversity in our current GenBank database and limitations of the current search algorithms. We are currently ill-prepared to deal with novel pathogens (natural or engineered), complex mixtures of organisms, or detection of virulence regardless of the organism conferring it. This problem is compounded by our near-total lack of knowledge of “normal” viral backgrounds in environmental, human, and agricultural samples.
The present invention provides a system for taking a complex sample and isolating individual single or double stranded nucleic acids within their own subnanoliter size reactors, amplifying the target nucleic acid through PCR, sorting out nucleic acid from non-nucleic acid reactors, and characterizing the selected nucleic acid reactors through capillary electrophoresis. The present invention also allows the detection and characterization of novel viruses and organisms by allowing the sequencing of previously unknown genetic material. The present invention allows for: reduction of costly reagent volumes, production of massively parallel and inexpensive microfluidic analysis chips, and scalable mass production of such chips. Technologies that could compete with the present invention are mainly robotic-based systems. These devices typically couple auto-pipettes with robotic manipulators to measure, mix, and deliver sample and reagents. These devices are relatively complex, expensive, and difficult to miniaturize.